Sleep apnea can result in frequent periods of decreased oxygen levels in the body, known as intermittent hypoxia.

Just six hours of the fluctuating oxygen levels associated with sleep apnea can begin to deteriorate a person’s circulatory system, the study found.

“While it is well established that sleep apnea is linked to high blood pressure, our study shows this condition has an impact on the cardiovascular system that can begin within a single day,” said researcher Glen Foster, Assistant Professor at University of British Columbia’s Okanagan campus in Canada.

“After just six hours of fluctuating oxygen levels, similar to what happens with sleep apnea, the body’s ability to regulate blood pressure is impaired,” Foster noted.

“These changes occurred almost immediately in healthy young adults who were not experiencing the cumulative effects years of sleep apnea could bring about,” Foster said.

As part of his study, Foster examined the impact of intermittent hypoxia on the cardiovascular system in a few healthy young adults.

Study participants wore a ventilating mask for six hours and oxygen levels were altered to mimic sleep apnea symptoms.

The study, published in the American Journal of Physiology, found that sleep apnea compromised the function of a person’s baroreceptors–biological sensors that regulate blood pressure.

It also found damaging blood flow patterns in the legs, which over time could impact vascular health.

“These findings suggest that interventions for people suffering sleep apnea should occur as soon as the condition is diagnosed,” Foster said.